Collaboration sessions hosted by a server often use multicasting to transmit the data of the collaboration session. As the number of attendees of collaboration sessions increase, and as the development of automatic multicast tunneling (AMT) technology has progressed, servers often use source-specific multicasts (SSM) with AMT technology to send the data of the collaboration sessions. The combination of the AMT technology with SSM reduces the outbound bandwidth and the costs for the server and the data center to host the collaboration sessions. Collaboration servers usually send data via different SSM channels having a variety of different bit rates to attendees experiencing different network conditions. However, this often causes attendees to receive data at a bit rate that is much lower than what the attendee is capable of receiving, resulting in a degraded user experience resulting from latency, poor media quality, or both.